Stick applicators having various dispensing structures are generally known as being useful for dispensing various products including lip balms, lipsticks, deodorants, and the like. Stick applicators may take the form of, for example, a roll-on applicator for a liquid or a screw-operated push-up applicator for a non-liquid substance.
In a typical screw operated push-up applicator, material is stored within a barrel and is supported by an internally threaded elevator. A rotatable dispensing screw extends longitudinally inside the barrel and engages the elevator. The screw has a control knob, located at a non-dispensing end of the barrel, that determines the elevator's position. When the knob is turned, the screw is rotated inside the barrel causing the elevator to travel longitudinally, and push the material out of an opposite (dispensing) end of the barrel.
In another embodiment of a screw-operated push-up applicator, the control knob is non-rotatably fixed within an outer container surrounding a barrel, such that upon turning the barrel itself by a collar on the opposite end has the effect of moving the elevator within the barrel. This structure is described in U.S. Pat. No. 5,842,802.
Known roll-on applicators have a rotatably suspended ball that carries a liquid material on the ball surface from a barrel interior to an exposed exterior.
Dual dispensing applicators have been proposed in the past. However, existing dual applicators are cumbersome and complex in structure and use. In some known devices, for example U.S. Pat. No. 3,690,777, the material to be dispensed is stored in removable closures instead of being held in the barrel itself. Removal of a closure from either end reveals an applicator tool used to remove and apply material stored inside the closure. Thus, the closure and applicator must each be maintained separately during use. Each closure serves both a reservoir function and a closure function. In another dual applicator device, as disclosed in U.S. Pat. No. 2,710,614, a duplex rotary holder has guide pins on carrier members that interact with rotating sleeves having helical slots. When one of the sleeves is turned, its respective slot pulls the guide pin causing the carrier to move longitudinally to dispense a solid material.
It would be desirable to have a dual applicator stick that integrates existing individual applicator assemblies in a dual pack configuration so that two separate product volumes are readily available to a user in a single package.